Can not boot from USB anymore

Hello Guys,

i did my second attempt of installing macOS on my PC two days ago. Following the Mojave guide from tonymacx, I started by setting up a bootable Stick via Unibeast. After that I loaded the Default UEFI settings of my GigaByte Z97 HD3 MB and only disabled VT-d afterwards. Unlike on my first attempt, I did not get stuck while installing, and it seemed to work. After the installation finished I got an error stating that my "drive space" was too low (I tried to install it on an empty 250GB SSD for it so the error was a bug). Anyways, I thought I might just try again. Now the Problem is: I can not boot from my USB anymore. Things I tried yet:
-Create the USB with "sudo /Applications/Install\ macOS\ Mojave.app...." + Clover.
-Tried several different USB hubs.
-Tried if I can create and boot a USB Stick with some Linux distro (that worked).
-Tried several other USB sticks (no succes).

One other thing which i find somewhat weird is that, even though I completely erased my SSD, it still shows 2 options to boot macOS (see picture) in my boot-options. When trying to boot into one of those I end up in Ubuntu tho.

Any ideas?

My system is:
CPU: i5 4670k
MB: gigabyte z97 hd3
GPU: asus gtx 1060